CfA Colloquium Schedule Fall 2011
 
 15 September 2011

15 September 2011

Speaker: Lisa Kewley (IfA, Hawaii)

Title:Galaxy Formation and Evolution through Metals

Abstract: Chemical abundances in galaxies provide a fossil record of previous generations of star formation, modulated by galactic-scale gas flows. I will present the latest results from our investigation into the chemical evolution of galaxies, both locally, and at high redshift. Theory predicts that as a merger progresses, galaxy disks become disrupted by tidal effects, causing large radial gas flows toward the central regions where kpc-scale starbursts and AGN may be fueled. Isolated disk galaxies have strong chemical abundance gradients that may become disrupted during a merger. We have conducted the first investigation into chemical abundance gradients across the merger sequence. We show that abundance gradients evolve dramatically with merger progress, providing a smoking gun for galactic-scale gas flows in merging galaxies. Moving out in redshift, I present recent results from our investigation into the cosmic chemical history of galaxies. We have measured the chemical abundances for an unprecedented number of galaxies to z~1, finding little evolution between z~1 and the present day. At higher redshift, we exploit the power of gravitational lensing to investigate the chemical evolution in galaxies between 1 < z < 3. We have measured the first metallicity gradient in a normal spiral galaxy at z~2, showing a steeper gradient than observed in local spiral galaxies. I will discuss the implications of this result and the future of this field with the next generation of telescopes.

Video of the Presentation (Talks can be viewed with RealPlayer. Free download is available from www.real.com )

 
 

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